Phonographic translating device



May 20, 1941. R. M. soMERs PHONOGRAPHIC TRANSLATING DEVICE Filed 001'.. 27, 1939 .5,7 59 'F' Snuentor Rickard Momers Patented May 20, 1941 UNITE STTS to Thomas A. Edison,

Incorporated, West Orange, N. J., a corporation of New Jersey Application October 27, 1939, Serial No. 301,548

21 Claims.

This invention relates to translating devices for phonographs and more particularly to phonographic recorders. The invention is especially concerned with new and improved means for stabilizing (i. e. suppressing undesired vibrations in) phonograph'ic recorders of the type which operate by cutting or impressing modulated grooves in and yalong the surface of a record body. In some respects the invention has relation to phonographic translating devices of the combined rrecording and reproducing type.

Recordations of the form above mentioned may be effected by means of a recorder unit comprising a recorder stylus, a vibratile means, yand a holder for the stylus and vibratile means which is mounted, usually as by a pivoting thereof to a carriage, for movement towards and away from the record. The recorder stylus is biased into contact with the record and is vibrated in accordance with sound waves so that when a relative progressive movement is effected between the stylus and the record there will be formed in and along Vthe record material `a progressive groove bearing sound-representing modulations.

The depth of groove is usually controlled by either of two methods: rst, a method involving the gauge principle wherein Ithe recorder unit is biased heavily towards the record and an advance ball arrangement is provided to limit the depth of groove made by the recorder stylus; and second, a meth-od involving the floating principle wherein the recorder unit is biased relatively lightly towards the record and this biasing is counterbal-anced entirely by the force exerted upon the stylus due to its coaction with the moving record. The iirst of these methods is impractical in many applications because of the highly critical nature of the adjustment required between the advance ball and the recorder stylus; the second of these methods does not entail such highly critical adjustments and in general is the more desired method.

There is, however, a tendency for phonographic recorders employing the floating principle to become instable. This instabilitywhich is in the nature of a vibration of the recorder unit, as a whole, relative to the recordcauses the stylus to form a groove of irregular dep-th and in extreme cases to skip alo-ng the record surface to produce jump-outs. The cause for this instability is that the coacting recorder unit and moving record tend to form an undamped oscillatory system as between the effective mass of the unit and an effective compliance .arising from the coaction of the unit with the moving record. This effective compliance arises from the fact that as the depth of groove made by the recorder stylus is increased the force which urges the stylus out of the record is likewise increased-i. e., there is a direct proportionality between the displacement of the stylus into the material of the moving record and the force which resists such displacement. While a very careful adjustment of the Ipivoting of the recording unfit is often helpful in overcoming the instability of the recorder it is found unsafe to rely upon such adjustments in commercial devices.

To overcome recorder instability of the type above mentioned damping has been applied between the recorder unit and the frame to which it is pivoted. The application of damping to the recorder unit in this manner has, however, entailed serious dimculties. One of these difficulties is that the application of damping between the recorder unit and the frame to which it is pivcted acts to hinder the recorder unit from freeiy following the surface of the moving record, Although movements of the unit in following the record are slow relative to the movement of the unit when vibrating at its frequency of instability (such following movements being only a few cycles per second at-the most), yet this hindrance may be particularly great when frictional damping is employed since friction-al damping has not only a characteristic linear with velocity but also a high static coefficient The application of Viscous damping between the recorder unit and frame is, however, more suitable than that of frictional damping since viscous damping has a characteristic which increases with velocity. This kind of characteristic permits a relatively large damping effect at higher frequencies, where instability usually occurs, without resisting the movement of the recorder unit at low frequencies sufficiently t-o prevent the unit from following the surface of the movin-g record. But the usual viscous damping means has inherent limitations which greatly restrict the applications in which it may be advantageously employedl In the usual phonographic recorder, the recorder unit must necessarily have a large range of movement relative to the frame in order to accommodate both highr and low records and to permit the unit to be moved free of the record to place `the translating device int-o inoperative condition. Such large relative movements tend to have disturbing effects upon the'viscous damping means with the result that a non-uniform damping action is obtained throughout the use of the translating device.

I-t is an object of my invention to provide improved means for stabilizing the recording action of phonographic translating devices, and particularly to avoid such defects as are above mentioned in connection with heretofore known stabilizing arrangements.

It is another object of my invention to render such stabilizing means dependable :and highly uniform in action, yet without adversely affecting the overall operation of the translating device.

It is another object of my invention to provide a stabilizing system for a phonographic recorder in which frictional and/r viscous damping may be advantageously employed to effect new and improved results.

It is another object Iof' my invention to provide a new, improved and simplified relationship between the parts of a combined recording and reproducing translating device whereby to render the device stable in action when it is used as a recorder.

It is another object of my invention to provide means for stabilizing the action of phonographic recorders, which is unaffected by unevenness in the surface of the moving record or by a placing of the recorder into operative and inoperative conditions.

Another object of my invention is to stabilize the action of a phonographic recorder by the provision of viscous damping between the recorder unit and a movable member which is so controlled as to elect a uniform damping effect on theunit.

Another object is to stabilize the action of a phonographic recorder by the control of a biasing of the recorder against the record.

A feature of my invention is to provide damping between the recorder unit and a member which is supported Yto move in conformity with the surface of the moving record and which is maintained in substantially the same spaced relationship to the recorder unit when the record is placed into operative and inoperative positions.

Another feature of my invention is to provide arecorder unit which is partially supported by sliding contact with the moving record at a point in advance of the recorder stylus and f through a damped compliance.

Other and allied objects and features of my invention will more fully appear from the following 'description and the appended claims.

In the description of my invention reference is had to the accompanying drawing, of which:

Figure l is a vertical sectional View of a portion of a phonograph showing a phonographic translating device in which one form of my invention is incorporated;

Figure 2 is a top view of the translating device with parts in section along the line 2--2 of Figure l; Y

Figure 3 is a vertical view, partly in section l and partly broken away, of a phonographic translating device incorporating a modied form to that of Figure 3 but showing another modication of my invention as'applied to the translating device;

Figure 6 is a top View to enlarged scale of a portion of the mechanism shown in Figure and F Figure 7 is a vertical section view taken substantially along the line 'I-'I of Figure 6.

Reference being had to Figure 1 there will be seen a portion of a commercial phonograph or dictating machine comprising a carriage I which is mounted for movement along a record 2, the mounting for the carriage being shown in part and comprising a sleeve I which slidably embraces a rod 3 that extends along the record. The carriage is provided with an apertured arm t extending forwardly over the record and carrying a phonographic translating device 5 which is arranged for coaction with the record. A relative progressive movement between the translating device and record is effected by a rotation of the record and a concomitant feeding of the carriage therealong. The feeding means for the carriage comprises a rotatable feed screw 6 which extends along the path of the carriage. Connection of the carriage to the feed screw is made by means of a feed nut 'I carried by an angle iron 8 which is pivoted on a rod 9 to the carriage. During operation of the machine the feed screw 6 and record 2 are rotated concurrently as by a suitable drive means not herein necessary to show.

The feed nut 'I is biased into engagement with the feed screw 5 but is movable at will out of engagement with the feed screw to free the carriage for manual movement along the record. rI'he biasing of the feed nut is effected by means of a tension spring Iii connected between an arm 8 on the angle iron 8 and a pin II on the carriage. The disengagement of the feed nut from the fee-d screw is controlled by a lever I2 extending upwardly through an opening I3 in the top of the carriage and having a hub I2 which embraces the sleeve I. On the hub of the lever I2 there is a projection I 4 carrying a cross pin I5 which overlies a forwardly extending arm I6 on the angle iron 8. When the lever I2 is in a forward position, as shown in Figure l, as well as in its most rearward position, the pin I5 is free of the arm I and the feed nut I is then held in engagement with the feed screw E by the spring I9. However, as the lever I2 is moved from either its forward or rearward positions into a central position the arm I6 is cammed downwardly by the pin I5 so as to disengage the feed nut from the feed screw. This central position of the lever I2 is defined by the engagement of the pin I 5 with a notch Il on the arm It.

While my invention is primarily concerned with the provision of improved means for stabilizing the action of phonographic recorders, I nd that my invention may be very simply and advantageously incorporated in'- phonographic translating devices of the combined recording and reproducing type. For this reason I illustrate the sound translating device 5, in which my invention is incorporated, as being of a type selectively conditionable for recording or reproducing. 'Ihis type of device may have a recorder stylus I9 and reproducer stylus 2i! selectively movable into contact with the record to condition the device for recording and reproducing. When the translating device 5 is conditioned for recording it is adapted to receive soun-d Waves by way of a neck I8 and impart an undulating movement in correspondence With the sound waves to the recorder stylus I9, and when the translating device is conditioned for reproducing it is adapted to create sound waves in correspondence with undulating movements imparted tothe reproducer stylus 2f! as by the tracking of the stylusalong a modulated groove in the record 2.

The translating dev-ice 5 comprises a frame 2| in the form of an inverted cup. This frame is provided at its center with the upwardly extending neck I8 above mentioned and at its forward end with a downwardly extending lug 22. Positioned below the frame 2| is a circular casing 23 having an apertured dome 23' centrally thereof and a turned-down flange 24 at its rim (see Figure 7). Fitting the ange 24 is .a g-asket 25 embracing a vibratile means or diaphragm 26 which closes the bottom of the casing. Thus within the casing 23 there is formed a chamber. This chamber is sound-coupled to the neck I8 by means of a tube 21 having an upper outwardly anged end portion 21 slidably fitting the inner wall` of the neck |8 and a flower outwardly flanged end portion 21" fitting the dome 23. This lower end portion is connected to the dome 23 to form a universal joint, the connecting means being lhowever not herein necessary to show. Connected to the diaphragm 2B is a stirrup 23 on which is mounted the recorder stylus I9. By this arrangement sound wave-s which are fed into the neck |8 are conducted into the casing 23 to set the diaphragm 26 into vibration, thereby causing the recorder stylus to lbe vibrated in correspondence with the sound waves.

The casing 23 is pivoted to the lug 22 for movement towards and away from the record. This pivoting is `effected by means of a bracket 23 terminating into a pair of spring arms 29 spaced from each other and having apertured end portions engaging conical ends oi a cross pin 30 carred by the lug 22 at its lower end portion. The spring arms 23 are biased away from each other but the spacing between the arms is controlled to lobtain the desired pressure of the arms on the conical ends of the pin 30 by means of an adjusting screw 3| which passes freely through one of the arms .and threads into the other.

The reproducer stylus 20 is mounted on a lever 32 which is pivoted, as at 33, to a biasing weight 34 for the reproducer stylus. The weight 34 is in the shape of a circular' disk having a central opening 35 through which the stirrup 28 may pass. The lever 32 passes through a slot 36 in the weight and terminates at apoint within the stirrup 28, as shown in Figure 3. The weight 34 is pivoted by a shoulder screw 31 to an arm 38 which in turn is pivoted on the pin 30 centrally thereof, the arm passing through a slot 39 provided in the lower end portion of the lug 22. By this means the weight 34 is pivoted for both radial and lateral movement relative to the record, the radial movement being about the pin 30 and the lateral movement about the screw 31.

It is seen that both the casing 23 and weight 34 are movable radially with respect to the record and are biased theretowards .by their own weights. To condition the translating device 5 for recording both the casing 23 :and weight 34 are permitted to move downwardly until each is supported by the record, thecasing being supported by way of the recorder stylus I9 andthe weight 34 by way of an advance ball 4I on the weight. Thus both the casing 23 :and biasing weight 34 are permitted to float on the record, the weight 34 however playing no part in recording. The mean depth of the groove, formed by the lrecorder stylus as a relative. progressivemovementy is` effected between the .translating .device and the record, is determined by the. force with which the recorder stylus is biased towards the record. Since practical limitations may requirey that the weight of the casing 23 be more than is needed to provide the Idesired biasing of the recorder stylus :against the record, the weight of the casing may be counterbalanced in part by a weight 42 which is in the form of an annular disk positioned above the casing 23 and surrounding the tube 21. This weight is pivoted as at 43 to the frame 2| and is connected by a link 44 to the casing 23, the link being pivoted to the weight 42 :as at 45 and to the casing about the adjusting screw 3 I.

When the translating device is conditioned for reproducing the casing 23 is retained in a raised positie-n and the 'biasing weight 34 is permitted to float in an intermediate position wherein it is supported by way of the lever 32, one end of the lever being supported by the contact of the reproducer stylus 2li with the record and the other end being supported by its contact with the stirrup 23.

When both the casing 23 and biasing weight 34- are maintained in raised position, both the recorder stylus i9 and reproducer stylus 20 are heldout 'of operative relationship (i. e., out of contact) with the record, to place the translating device in an inoperative condition.

The means for selectively placing the translating device 5 into inoperative condition and respective operative conditions for recording andreproducing comprises a pair lof lifting ngers 4B and 41 respectively :adapted to contact a tab 48 on the casing 23 and a lug 49 on the biasing weight 34 to hold the casing and biasing weight in raised position. The fingers 46 and 41 are pivoted on the rod 9 `and are each biased upwardly by means of tension springs connected between the rod II and short arms extending upwardly from the pivoting iaxis of the fingers, the spring and arm which `form the biasing means for the finger 41 being represented as 50 and 5| respectively. The positioning of the iingers is, however, controlled by the lever I2. When the lever I2 is in a forward position both fingers are held in downward position by the pin i5, thereby permitting the casing 23 and biasing weight 34 to move downwardly on the record to effect the recording condition of the translating device. As the lever I2 is moved into its central position the pin I5 slides along c-am faces 52 on the fingers to permit each of the fingers to move upwardly in respon-se to their biasing, thereby placing both the casing 23 and biasing weight 34 in raised position to effect the inoperative condition of the translating device; and as the lever i2 is moved into its rearward position the pin i5 remains free of the finger 43 but encounters a cam face 53 on the iinger 41 to move this finger downwardly, thereby causing the casing 23 to be retained in raised position and permitting the biasing weight 34 to move downwardly into a lower position to effect the reproducing condition of th-e translating device. The lever I2 may be releasably held in its rearward position by the engagement of the pin i5 with a notch 54 provided in the linger 41.

As hereinbefore noted, when the recorder unitwhich unit comprises the casing 23, diaphragm 26, stirrup 23 and recorder stylus |9-is permitted to oat upon the surface of a moving record, its coaction with the surface of the record is of the nature of a compliance, which compliance reacts with the effective mass` of. therecordel' unit to form an essentially undamped oscillatory mechanical system. When mechanical oscillation of this system-i. e., vibration of the recorder unit-occurs, a groove of irregular depth is formed in the record body. Efforts to overcome tendencies toward such mechanical oscillation by the application of damping to the recorder unit-as between the unit and the frame to which it is pivoted-has acted to hinder the recorder unit from following the surface of the moving record. While for a given stabilizing effect such hindrance is less when viscous damping is employed instead of frictio-nal damping, yet the amount of viscous damping which may be employed is distinctly limited. Also the nature of the usual viscous damping means is such that viscous damping is not well suited to this 'particular application. For example, when there is employed the well-known form of viscous damping means comprising a vane movable within and relative to a container which is filled with a viscous substance, the vane being for example mounted on the recorderunit and the container on the frame, then relatively large movements of the vane relative to the container, as caused by movements of the recorder unit to accommodate high and low records and to place the phonographic recorder into operative and inoperative conditions, act to displacev the viscous substance out of the path of the vane. Such displacement of the viscous substance causes the viscous reaction to be great-v ly altered and at times to be reduced to a negligible value.

In accordance with my invention diflculties which have been encountered in stabilizing the action of phonographic recorders-such as are above mentioned-are obviated by the application of damping between the recorder unit and a movable member which is supported so as to be normally maintained in substantially the same spaced relationship to the recorder unit. My invention contemplates this movable member being so controlled as to move coordinately with the recorder unit in movements of the latter in following the record as well as during the placing of the recorder into its operative and inoperative condition. From another viewpoint my invention contemplates that this movable member be supported so that it will normally move coordinately with the recorder unit in movements of the latter at frequencies of the order of a few cycles lper second, such as those of the unit in following the surface of the moving record, but so that it will not move with the unit at higher frequencies approaching the natural frequency of instability of the unit, which frequency may typically be of the order of 70 or more cycles per second. A movement of this member in conformity with the movements of the recorder unit in following the surface of a moving record may be readily effected by permitting the movable member to be supported by and to glide over the surface of the record. In the combined recording and reproducing translating device as heretofore described, the biasing weight 3G constitutes such a movable member. Thus, to apply my invention to the translating device above described I need only apply suitable damping between the casing 23 of the recorder unit and the biasing weight 34. In the embodiment disclosed in Figures 1 and 2 the Adamping between the casing 23 and biasing weight 34 is of a viscous nature and is obtained by the provision of a cup 55 on the welght 34 which is partially lled with a viscous substance 55,vsuch as oil or vaseline, and into which a vane 56 carried by the casing 23 is extended. With'this arrangement the damping applied to the recorder unit does not act to hinder the unit from following the record since the casing 23 and biasing weight 34 are maintained in substantially the same spaced relationship during the operation of recording by reason of each being floated upon the surface of the moving record. Also a uniform spaced relationship is substantially maintained as the translating device is shifted into inoperative condition and back into condition for recording. Thus the viscous substance 55 in the cup 55 is undisturbed by the movements of the recorder unit in following an uneven record or by the shifting of the translating device between inoperative condition and a condition for recording on either high or low records, thereby permitting a uniform damping action to be obtained.

In utilizing the reproducer stylus biasing weight as a part of the system for stabilizing the action of the translating device when it is used as a recorder, some disturbance of the viscous substance in the cup 55 is caused when the device is conditioned for reproducing, by reason of the relative movement between the casing 23 and biasing weight 34 accompanying such conditioning of the device. This relative movement is, however, small compared with the movements of the casing relative to the frame to which it is pivoted, and the extent of the disturbance of the Viscous substance in the cup 55 is therefore also small compared with that which is obtained when damping is applied between the recorder unit and frame. The small disadvantages arising from such disturbances of the viscous substance are considered to be more than outweighed by the advantages arising from the simplications in structure which are incidental to utilizing the weight 3d as part of the stabilizing system.

In Figures 3 and 4 there is shown a second embodiment of my invention employing frictional damping between the casing 23 and biasing weight 34. 'Ihis frictional damping may be conveniently obtained at the pivots of the casing and biasing weight while yet permitting free pivotal movement of both the casing and biasing weight relative to the frame. In the present instance such pivoting is obtained by journalling the pin 30 in the lug 22, fastening the arm 38 of the biasing weight 34 to the pin 30 as by means of a set screw 5i), and then adjusting the pressure of the spring arms 29 on the conical ends of the pin 3U, as by the adjusting screw 3l, until the desired frictional reaction is obtained between the casing and the weight.

It will be understood that the instant invention is one to which frictional damping is particularly well suited, since the high static coefficient of frictional damping acts to inhibit relative movement between the recorder unit and biasing weight 34. Moreover, this frictional damping does not impede the recorder unit from following the record since both the unit and weight are floated upon the record to move in conformity with the surface of the record.

In Figures 5, 6 and 7 there is shown a third embodiment of my invention employing a free pivoting arrangement between the recorder unit and biasing weight 34, as in my first embodiment, but dispensing with the counterbalance on therecorder unit as provided by the Weight 42 of the prior iigures. That excess part of the weight of the recorder unit which was relieved from the recordby the counterbalancing weight 42 is now, however, taken up by the biasing weight v314 through a vdamped compliance. The means -for obtaining this damped compliance comprises a circular recess 51 in the biasing weight 34, which is closed at the bottom by a screw plug 58 and provided with a restricted opening l at the top. Into this opening there is fitted aihollow plunger 59 having an outwardly fianged rim 59 at its bottom slidably ntting the recess and acting to limit the upward movement of the plunger. The plunger 5d is biased upwardly by'a helical compression spring Si! interposed between the top of the plunger and the plug 58 and about an axial stem 6l on the plunger. Within the plunger and about the spring 60 and stem 6I there is provided a suitable viscous substance 69 for damping the movement of the plunger.

During the operation of recording the rim of the casing 23 rests on the top of the plunger 59 to cause a substantial portion of the weight of the recorder unit to be relieved from the recorder stylus by way of the advance ball 4I. Although the depth of groove is here in part controlled by an advance ball system it will be found that the groove depth is not critical to a variation in positioning of parts of this system since I relieve the excess weight of the recorder unit from the record through a considerable compliance as by means of the spring 50. When the compliance of this spring is made large, the excess weight of -the recorder unit being then relieved from the record by a substantial compression of this spring, small displacements between the casing and 4biasing weight do not cause the force taken up by the spring 53 to be greatly altered. Thus should the recorder stylus shift in position relative to the point on the casing 23 which contacts the plunger 59, the force with which the recorder stylus presses against the record will not be altered sufficiently to cause a substantial change in groove depth.

If in the arrangement constituting this third embodiment, an instability or vibration of the recorder unit is started by a sudden displacement of the unit, then the casing 23 will break Contact with the plunger 59 during the upward movement Vofthe unit since the plunger is prevented from following the casing in response to the spring 6G by reason of the viscous substance Bil. The breaking of contact with the plunger 59 immediately causes the upward movement of the unit to be checked since this breaking of contact results in an overbiasing of the unit against the record.

Damping applied to the plunger 59 in an amount suincient to cause the plunger to break contact with the recorder unit upon a sudden upward movement of the unit away from the biasing weight 34, may however not be sufcient to cause an effective counteraction of a downward movement of the unit towards the weight'34. While it is found that the recorder is rendered stableA when the plunger is damped just sufficiently to cause it to break contact with the recorder unit in the manner here described, I may, if desired, obtain an additional stabilizing influence on `the recorder by applying sufficient damping to the plunger 59 to cause an effective counteraction of downward movements of the recorder unit. Thus both downward and upward movements of the recorder unit relative to the record may be effectively counteracted and checked to produce a highly stabilized recorder.

Although I have herein illustrated and `described my invention in terms of certain preferred embodiments it will be understood that these embodiments are illustrative of my invention and not limitative thereof as they are subject to many modifications and changes without departure from the scope of my invention, which scope I endeavor to express according to the following claims'.

I claim:A

l, In a phonographic recorder comprising a frame, a stylus and means tending to force the stylus into a moving record body to form a rgroove in the surface layer of the body: the combination of a holder supporting said stylus for vibration relative thereto and movably mounted on said frame to permit the stylus to track the record surface; a member movablyfmounted on said frame and moved in conformity with variations in the level of the record surface traversed by the recorder; and damping means comprising two separate elements coacting to resist relative movement therebetween, the kpair'of said eleholder and said member Vwhereby to resist movements being operatively interposed between said ment of the holder relative to the level of the traversed surface of the moving record body.

2. In a phonographic recorder `comprising a frame, a stylus and means `tending toY force said stylus into a moving record body to 'form Va groove in the surface layer ofthe body: the combination of a stylus holder yiel'dably connectedY to said stylus and movably mounted on said frame to permit the stylus to track the moving record surface; a member movably mounted on said'frame and moved at least substantially in conformity with `variations lin the level of the traverse'dsurface of the moving record; and stabilizing means for the recorder adapted to prevent vibration of said Aholder relative to the moving `record surface, comprising damping means operatively connected between said holder and member.

3. In a phonographic recorder comprising a frame and a stylus biased toward a moving record body: the combination of a holder for said stylus movably mounted on said frame to permit the stylus to track the surface of the moving record; resilient means connecting said stylus to said holder and causing the holder to move in conforrnty with the stylus in record-tracking movement of the latter within a lower frequency range; a member movably mounted on said frame and moved in conformity with low-frequency variations in the level ofthe traversed surface of the moving record whereby to cause the memer to move coordinately with said holder in movements of `the latter throughout said lower frequency range; and damping means associated with said holder and said member and providing a substantial resistance to movements of said holder relative to said movable member at freduencies above said lower frequency range.

4.111 a phonographi'c recorder comprising a stylus and means tending to force the stylus into a moving record bodyl to form a groove in the surface layer of the body: the combination of a holder for said stylus movably mounted to permit the stylus to track the moving reoordsurface; resilient means connecting said stylus to said holder to permit vibration of the stylus relatively to the holder throughout an upper frequency range, said resilient means causing the helder to move in conformity with the stylus in tracking movements of the latter throughout a lower frequency range; a movably mounted inertia member slid on the surface of the moving record body in advance of said stylus; and viscous damping means including a viscous substance operatively interposed between said holder and said inertia member for damping vibrations of said holder relative to said inertia member at frequencies within said upper frequency range.

5. In a phonographic recorder comprising a stylus and means tending to force said stylus into a moving record body to form a groove in the surface layer of said body; the combination of a stylus holder yieldably connected to said stylus and pivoted to permit the stylus to track the surface of the moving record; a pivoted inertia member slidable on the surface of the moving record; and damping means between said holder and inertia member for damping relative movements therebetween.

6. In a phonographic recorder comprising vibratile means adapted to coact with the surface of a moving record: the combination of a holder for said vibratile means movably mounted to permit the vibratile means to track the surface of the record; Va movably mounted inertia member supported by sliding contact with the surface of the moving record; and stabilizing means for the recorder, comprising surfaces respectively associated with said holder and inertia member and coacting to produce a damping effect upon said holder, whereby to resist vibration of the holder relative to said inertia member.

'7. In a phonographic recorder comprising vibratile means adapted to coact with the surface of a moving record: the combination of a holder for said vibratile means pivoted to permit the vibratile means to track the surface of the record; pivoted inertia means biased into sliding contact with the surface of the moving record; a device having relatively movable portions respectively operatively associated with said holder and movable means; and a viscous substance, mutually associated with said relatively movable portions,

for causing a viscous reaction therebetween.

8. In a phonographic translating device having vibratile means and recorder and reproducer styli associated with said vibratile means and respectively movable into contact with a record to condition said device for recording and reproducing: the combination of a movably mounted holder for said vibratile means; a movably mounted inertia member for biasing said reproducer stylus into contact with the record, said inertia member being urged towards the record and being released to slidingly contact the record when the translating device is conditioned for recording; and damping means for stabilizing the recording action of the translating device, comprising a pair of relatively movable parts respectively associated with said holder and inertia member and damped against relative movement therebetween 'whereby to damp said holder against vibration relative to said inertia member.

9. In a phonographic translating device having recorder and reproducer styli respectively movable into contact with a record to condition the translating device for'recording and reproducing': the combination of a holder supporting said recorder stylus for vibration and movable to bring the recorder stylus into contact with the record; biasing means for said reproducer stylus urged towards the record, and released to slide upon the surface of the record by the condition- Aing of the translating device for recording; a device having relatively movable portions respectively operatively associated with said holder and biasing means and positioned adjacently of each other at least when the translating device is in recording condition; and a viscous substance for causing a viscous reaction between said portions when they are in said adjacent relationship to each other.

10. In combination, a vibratile means having a holder pivoted to permit the vibratile means to track the surface of a moving record: a pivoted member biased towards the record and controlled in position by sliding contact with the moving surface of the record; a pair of adjacent members respectively operatively associated with said holder and pivoted member; and a viscous substance interposed between said adjacent members, whereby to cause a viscosity coupling between said holder and pivoted member.

11. In a phonographic recorder having a frame and vibratile means adapted to coact with the surface of a moving record: the combination of a holder for said vibratile means pivoted on said frame; an inertia member pivoted on said frame and slid on the surface of the moving record; and frictional damping means coupling said holder to said inertia member, comprising slidably coacting surfaces respectively associated with the holder and inertia member.

12. In a phonographic recorder having a frame and vibratile means adapted to coact with the surface of a moving record: the combination of a holder for said vibratile means pivoted on said frame; an inertia member pivoted on said frame and slid on the surface of the moving record; and frictional damping means coupling said holder to said inertia member, comprising slidably coacting surfaces respectively associated with the holder and inertia member, and further including adjustable means for controlling the pressure between said coacting surfaces.

13. In a phonographic recorder having a frame and vibratile means adapted to coact with the surface of a moving record: the combination of a holding member forsaid vibratile means; a movable inertia memberrbiased towards the record and slide along the surface of the record; a common pivotY for saidfmember journalled in said frame to permit pivotal movement of both said members relative to the frame and being journaled to one of `said members to permit relative pivotal movement between the members; and means adjustable to effect a predetermined frictional reaction between said members by way of said pivot, whereby to cause said members to be resisted against relative pivotal movement while yet permitting free pivotal movement of each relative to the frame.

14. In a phonographic recorder: Vthe combination of a movably mounted recorder unit including vibratile means adapted to coact with the surface of a moving record and means biasing said unit against the record in an amount in eX- cess of that required to maintain a normal coaction between the vibratle means and the record; counterbalancing means normally acting on said biasing means to relieve the biasing of said unit from the record by an amount to produce :a normal coaction between the vibratile means and the record; and means, associated with said bias-relieving means, for causing at least a substantial portion of the full biasing of said-unit against the record to be restored upon a sudden displacement of the unit from the record.

15. In a phonographic recorder: the combination of a recorder unit including a vibratable stylus biased inwardly into contact with the surface of a moving record in an amount in excess of that required to cause the stylus to form a groove of normal depth; means operatively associated with said recorder unit and normally relieving the biasing of said stylus from the record in an amount sufficient to cause the stylus to form a groove of normal depth; and movementresisting means, associated with said bias-relieving means, for causing at least a substantial portion of the full biasing of said stylus against the record to be restored upon a sudden outward movement of the stylus by the moving record.

16. In a phonographic recorder: the combination oi a recorder unit having a Vibratable stylus and biased towards the surface of a moving record in an amount in excess of that required to cause the stylus to form a groove of normal depth; a biasing means counteracting the biasing of said unit to cause the stylus normally to form a groove of normal depth; and damping means, associated with said biasing means and restricting the action of the same, for causing a damping reaction against sudden movements of said unit towards the record, :and also for causing a reaction against sudden movements of the unit from the record by a restoration of the full biasing of the unit towards the record.

17. In a phonographic recorder: the combination of a recorder unit mounted for movement towards and away from a moving record and including vibratile means and pressure means biasing said vibratile means into cooperative relationship with the record; and damped resilient means biased into Contact with said recorder unit and causing a damping of said unit in only one of its movable directions relative to the record.

18. In a phonographic recorder having vibratile means adapted to coact with the surface of a moving record: the combination of a movably mounted holder :for said vibratile means biased to urge the vibratile means into coacting relationship with the record; a movably mounted member biased towards the record into sliding contact therewith; resilient means interposed between saidl holder and movable member, said resilient means normally acting to relieve .a substantial part of the bias of said Vibratile means from the record; and a viscous substance associated with said resilient means for causing a viscous reaction against relative movement between the holder and movable member.

19. In a phonographic recorder: the combination of a movably mounted recorder unit positioned above a moving record and having Vibratile means biased by the weight of the unit into CII Contact with the surface of the record; an inertia member interposed between said recorder unit and the record and slidingly supported by the record; resilient means operatively interposed between said recorder unit and said inertia member and causing a substantial portion of the weight of said recorder unit to be supported by way of said inertia member; and means for causing a Viscosity reaction against relative movement between said recorder unit and said inertia member, comprising a device having relatively movable portions respectively associated with the recorder unit and the inertia member, and a viscous substance operatively associated with said movable portions.

20. In a phonographic recorder: the combination of a movably mounted recorder unit having vibratile means biased into coacting relationship with a moving record; a movably mounted member moved at least substantially in conformity with variations in the level of the traversed surface of the moving record; a device interposed between said recorder unit and movable member and having relatively movable portions respectively contacting said unit and member, said relatively movable portions being urged apart to normally relieve by a substantial amount the biasing of the recorder unit from the record; and a viscous substance associated with said movable portions and damping relative movement therebetween, whereby to cause the contact of said recorder unit and movable member with said .device to be interrupted and the full biasing of said recorder unit to be restored upon a sudden displacement of the recorder unit in the direction away from the record.

21. In a phonographic recorder: the combination of a movable recorder unit including vibratile means and pressure means biasing said Vibratile means into cooperative relationship with a moving record; a movably mounted member moved in conformity with variations in the level of the traversed surface of the moving record; means for damping said unit against vibration relative to the traversed surface of the moving record, comprising a pair of devices respectively associated with said unit and movable member, and a viscous substance mutually associated with said devices to provide a viscous reaction therebetween; and means for moving said recorder unit and movable member relative to the record to place the recorder into inoperative and operative condition, said means being controlled to eiect a substantially unitary movement of said unit and movable member whereby to preserve a uniform viscous reaction` between said recorder unit and movable member.

RICHARD M. SOMERS.

CERTIFICATE CE CORRECTION. Patent No. 2,2LI2,927. may 2o, 19in.

RICHARD .M soTIERs.

It is hereby Certified thaterror appears in the printed specification lof the above numbered patent requiring correction as follows: Page 5, seoond column, line 26, claim l, Strike vout the words and syllable "holder and said member whereby to resist moVe-" and insert the same after "said" in line 27 same claim; page 6, second column, line )47", Claim l5, for "slide" line )4.8 same claim, for "member" read Amembers; second column., line 55, Claim 2l, for the Word oo ndition" read --condiand that the said Letters Patent shouldbe readwith this Correcthat the same may conform to the record of the Case in the read --slrid-w;

tions;

tion therein Patent Office.

signed, and yAeA-Iles this 21pm day of June, A. D. 19m

Henry Van Arsdale (Seal) pas@ 7 Acting Commissioner of Patentslw 

